Traveling by steamboat in 1828, Capt. Basil Hall went as far as Balize, or Pilot Town, where he could see where the Mississippi's logs and silt ended up.
"In the spring when the freshes or floods come down, they bring millions of trunks of trees. In February and March, the quantity of these logs was so great, that not only the river itself, but the sea for several miles off, was so completely coated over with them, that it required some skill to get through.
"The whole ground; if the loose muddy soil could be so called; appeared to be formed of layers of these logs; matted together into a network, many yards in depth, over hundreds of square leagues.
"These enormous rafts of timber settle on the mud as the waters subside, are cemented together by fresh deposits. In a short time a rank sort of cane or reed springs up, which help to keep them together.
"This is called a cane brake, a wild, hopeless-looking, impassable sort of marsh. These reeds, by retarding the flow of the river, collect the mud of the next season, and by the process of their own decay, lend their share to form the alluvial soil of the Delta.
"Fresh logs, and fresh mud, and new crops of cane, go on forming for a certain course of years. At length a stunted, poor kind of shrub takes root and grows up in these slushy territories.
"When these trees grow up, they collect more soil about them, and land somewhat firmer is concocted, as we advance to the region of swamps from that of marshes.
"The intruder, man, now begins his operations by banking out the stream, and taking the further management of the soil into his own hands.
"Of course, all the sea-shores or skirts of the Delta of the Mississippi, must continue for a long time as useless marshes till fresh deposits raise the level a few feet more.
"It forms a curious speculation, I think, to inquire how far the system of making Levees on the sides of the Mississippi, may have the effect of modifying the form of the Delta.
"I had many opportunities of seeing how nature carried on her operations when left alone, and also how these were modified by the industry of man, who is gradually gaining, as he supposes, the complete mastery.
"The way in which the river proceeds to work is this. The country being very nearly level, and the surface every where formed of the finest (least coarse) materials, the river easily cuts its way through; and consequently we find in all such places, that the streams, wind about, and form themselves into knots, bends, loops, and a hundred fantastic shapes.
"In the ordinary course of things, there take place a series of scoopings in the concave parts of these bends, where the stream moves fastest, and a correspondent series of deposits on the convex sides, where it moves slowest.
"I may mention here an instance of the danger of tampering too much with such a prodigious monster as the Mississippi:"
Hall wrote of a property owner who devised a scheme to harness the natural land-building action of the river to increase the size of his riverside property.
"He got hold of some ten or a dozen of the great flat boats, and sunk them one by one in a line, at some little distance from the levee. This impediment to the course of the stream aided the deposits, and the land continued to rise with much greater rapidity than formerly.
"Our friend's fancy now reveled in the thoughts of the grand warehouses and wharves he was to build, till one night, 'souse' went his whole apparatus, carrying out of sight with it, in a couple of seconds, for ever and ever, not only all the extra land he had formed, but dragging with it a great part ..." of the silt built up naturally.
"Even the system of making levees is liable to the same chances. In ordinary times, the river goes on depositing mud at one place, and scooping away the soil at another.
"As long as the river does not reach the level of the country, all goes on regularly within its own channel; but during the freshes, when the water rises to the very brim, it must either flow over, along the whole bank, or cut its way through, and form new and wider channels. Where artificial levees are built, the river must cut through them to relieve the pressure of high water.
"The effect of such overflowings is most interesting. The larger materials, the coarser grains of the mud; are first deposited; then the less coarse, and so on. Thus, a sort of natural embankment, with a very gentle slope, is found to extend from the edge of such rivers, towards the swampy country on either hand.
"Each successive fresh that comes down, augments this bank, till a very perceptible rise is formed. There is, in many places, a gradual rise in the bed of the stream by the deposition of the heavier materials, the effect of which is to elevate the whole body of the river. It appears, indeed, that the Mississippi actually winds along the summit of a ridge.
"The whole Delta of the Mississippi is matted over with a web of rivers and bayous, along which are found these gentle slopes, crowned by an artificial levee, and protected from the annual inundations, yields crops of incredible richness. Sometimes, however, even there, the river gains the ascendancy, and forces its way through the levee by crevasses."
And when the levees succeed at holding the river, land-building ceases and wetlands disappear, as we have learned.